Many investors unwittingly abide by Wall Street's rules of engagement, thinking it's the only way to make money. But the Wall Street wise actually guarantee average Joe investors like you and me only one thing: Our interests matter less than their profits.

Wall Street is where the big dogs play -- Goldman Sachs, Merrill Lynch, JPMorgan Chase. But they play a game that's designed to give their banks all the money, leaving you holding an empty wallet.

The wingtip crowd has a long track record to support that claim. For instance:

  • They focus on the big money and do whatever they can to support those relationships. Their attention and research is geared toward deep-pocketed institutional clients, not average Americans and their retirement cash. When they overwhelmingly gave Yahoo! (NASDAQ:YHOO) a "strong buy" rating right before the tech bubble went pop, the Street crowd was hoping to make the institutional folks some fast cash. But when the bubble burst, we were the ones who suffered.
  • They maximize their own returns at the expense of individual investors. Wall Street firms make enormous profits from their venture-capital departments. So when they invest in a small, high-growth company, they'll often delay the IPO to get in on the action before they actually open the company up to the public. They tried to do this with Morningstar (NASDAQ:MORN), but the company withstood the pressure. Instead, Morningstar management -- in what was described as a maverick and foolhardy move -- issued the IPO via a Dutch auction, which leveled the playing field for small investors.
  • They can make markets. There is a supposed wall between research and investment-banking departments at Wall Street firms, but if you look closely, you'll see some fine print. Even on analysts' research reports, you'll often find that a company "makes a market in this security." By recommending positions in stocks in which they make a market, the Wall Street firms make money -- and analysts get higher bonuses. Remember that the next time you see recommendations for Salesforce.com at questionable valuations. Yes, the company dominated the customer relationship management market early on, but is it really going to grow at its current rates long enough to justify the expectations that are baked in to its current price? Many of the Wall Street banks want you to think so, but they get money no matter what you do.

I hate to break it to you, but unless you're among the minority of Americans with "high net worth," you're Wall Street's last priority.

Don't play by those rules
You need to understand that analyst recommendations are focused on the short term and geared toward big investors. Because analyst performance is measured on a quarterly basis, it needs to predict only three to nine months into the future.

If you look at the analyst estimates for a stock like SanDisk (NASDAQ:SNDK), you can see that many of the banks flip-flopped back and forth on their recommendations, even over a short time horizon.

Or take a look at eBay. One firm went from hold to sell to hold in less than a year. But can you hold shares you've already sold?

This phenomenon is visible in established companies with proven results such as Anheuser-Busch (NYSE:BUD) and Kraft (NYSE:KFT), with analysts' recommendations changing in fewer than six months -- even though blue chip stocks such as these perform best when held for the long term.

While there may be short-term reasons to justify these moves, my investing timeline is longer than that, particularly when I consider the commissions associated with rapid trading.

Be contrarian
It's difficult to buy in the face of a downgrade. We all fear losing money, but your portfolio will thank you if you can escape the short-term Wall Street cycle. One way to do this is to buy stocks that Wall Street doesn't even bother to follow.

Fool co-founder David Gardner did this when he recommended Marvel Entertainment (NYSE:MVL) to Motley Fool Stock Advisor subscribers in July 2002 -- when not a single analyst was covering the stock. Since then, Marvel has returned nearly 650%. Take that, Wall Street!

Guarantee yourself better returns
The only way to guarantee better returns is to invest your money with a person you trust completely. Many times, that person is you.

That's why we at The Motley Fool advocate that you take control of your own investing destiny. If you'd like to get started on this path, be our guest at the Motley Fool Stock Advisor newsletter service free for 30 days. You'll find ideas that directly contrast the Wall Street state of mind: a long-term investment horizon, full disclosure, and discussion boards that will give you the courage to be contrary. Those ideas are making subscribers of Stock Advisor a pretty hefty profit -- an average return of 73% compared with the market's 35% since inception in 2002.

This article was originally published March 3, 2006. It has been updated.

Fool contributor Shruti Basavaraj guarantees that they don't have Cake Day, a monthly Motley Fool occurrence, on Wall Street. eBay, Yahoo!, and Marvel are all Motley Fool Stock Advisor picks, while Anheuser-Busch is a Motley Fool Inside Value selection. Kraft and JPMorgan are Income Investor recommendations. The Motley Fool's disclosure policy is guaranteed.